Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
1.
J Ethnopharmacol ; 107(1): 83-90, 2006 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-16603327

RESUMEN

An aqueous decotion (dried extract), an 80% MeOH extract from Morinda morindoides leaves, and 10 flavonoids and 4 iridoids isolated from the 80% MeOH extract were evaluated in vitro for their potential antiamoebic activity and their cytotoxic effect against MT-4 cells. Results indicated that the aqueous decoction and the 80% MeOH extract exhibited an interesting antiamoebic activity with IC(50) values of 3.1 +/- 1.7 and 1.7 +/- 0.6 microg/ml, respectively. Apigenin-7-O-glucoside and luteolin-7-O-glucoside exhibited a moderate antiamoebic activity with IC(50) values of 22.3 +/- 3.2 and 37.4 +/- 2.7 microg/ml, respectively. Kaempferol (IC(50) = 10.3 +/- 2.3 microg/ml), apigenin (IC(50) = 12.7 +/- 4.3 microg/ml), and luteolin (IC(50) = 17.8 +/- 4.3 microg/ml) showed a more pronounced activity than their corresponding glycosides. All tested iridoids displayed a very good activity with IC(50) values less than 10 microg/ml. The most active iridoids were epoxygaertneroside (IC(50) = 1.3 +/- 0.4 microg/ml) and methoxygaertneroside (IC(50) = 2.3. +/- 0.7), followed by gaertneroside and gaertneric acid with IC(50) values of 4.3 +/- 1.8 and 7.1 +/- 1.4 microg/ml, respectively. Except quercetin and quercetin-7,4'-dimethylether which have shown a cytotoxic effect with IC(50) ranging from 14 to 22 microg/ml. No correlation could be deduced between the observed antiamoebic and cytotoxic activity of these tested samples. A structure-activity relationship for isolated compounds is discussed. These findings support the medicinal report for the traditional use of Morinda morindoides leaves for the treatment of amoebiasis.


Asunto(s)
Amebicidas/farmacología , Entamoeba histolytica/efectos de los fármacos , Morinda/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Animales
2.
J Ethnopharmacol ; 79(2): 213-20, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11801384

RESUMEN

The chemical composition of essential oils from 15 aromatic medicinal plant species growing in the Democratic Republic of Congo have been studied. More than 15 constituents in an amount higher than 0.1% were identified in each essential oil. 1,8-cineole, alpha and beta-pinene, p-cymene, myrcene, gamma-terpinene, alpha-terpineol and limonene were prevalent constituents in almost more than 10 selected plant species. Results from the antibacterial testing by the diffusion method indicate that all essential oils (5 microl per disc) inhibited the growth of selected bacteria at different extents. The most active antibacterial essential oils were those of the leaves of Eucalyptus camadulensis and Eucalyptus terticornis (12-30 mm zone diameter of inhibition). They showed particularly a most potent inhibition of Pseudomonas aeruginosa growth (15-16 mm), followed by Eucalyptus robusta (12 mm). Essential oils from the leaves of Eucalyptus alba, Eucalyptus citriodora, Eucalyptus deglupta, Eucalyptus globulus, Eucalyptus saligna, Eucalyptus robusta, Aframomum stipulatum, Cymbopogon citratus, Ocimum americanum and that of the seeds of Monodora myristica showed also a good antibacterial activity (10-18 mm). Eucalyptus propinqua, Eucalyptus urophylla and Ocimum gratissimum essential oils were the less active samples against the selected bacteria. No correlation between the amount of major constituents such as 1,8-cineol, alpha-pinene, p-cymene, cryptone or thymol and the antibacterial activity was observed.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Medicinas Tradicionales Africanas , Aceites Volátiles/química , Aceites Volátiles/farmacología , Antibacterianos/uso terapéutico , República Democrática del Congo , Evaluación Preclínica de Medicamentos/métodos , Evaluación Preclínica de Medicamentos/estadística & datos numéricos , Bacterias Gramnegativas/crecimiento & desarrollo , Bacterias Grampositivas/crecimiento & desarrollo , Aceites Volátiles/uso terapéutico , Fitoterapia/métodos , Fitoterapia/estadística & datos numéricos , Semillas/química
3.
J Pharm Pharmacol ; 53(5): 757-61, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11370716

RESUMEN

Bridelia ferruginea Benth. (Euphorbiaceae) is a subtropical medicinal plant widely used in traditional African medicine against various diseases, including rheumatic pains. Seven of its constituents (3-O-methylquercetin (1), 3,7,3',4'-tetra-O-methylquercetin (rutisin, 2), myricetin (3), 3',4',5'-tri-O-methylmyricetin (ferrugin, 4), 3,3',4',5'-tetra-O-methylmyricetin (5), quercetin 3-O-glucoside (6), and a biflavanol gallocatechin-[4'-O-7]-epigallocatechin (7)) have been evaluated in-vitro in the xanthine-xanthine oxidase enzymatic system for inhibition of xanthine oxidase and radical scavenging activity. Results indicated that compounds 1, 3, 4 and 6 exhibited, at different levels, xanthine oxidase inhibiting and superoxide scavenging activity at micromolar concentrations, whereas compound 7 showed scavenging activity only. Compounds 2 and 5 were inactive in both cases. Study of the structure-activity relationship demonstrated that for flavonoids the xanthine oxidase inhibitory activity was reduced by methylation of the hydroxyl functionality at C-3 and in rings A and B. These results may partly explain and support the use of B. ferruginea stem bark for the treatment of rheumatic pains in traditional medicine.


Asunto(s)
Depuradores de Radicales Libres/farmacología , Fenoles/farmacología , Xantina Oxidasa/metabolismo , Artritis Reumatoide/tratamiento farmacológico , Humanos , Medicinas Tradicionales Africanas , Fenoles/aislamiento & purificación , Extractos Vegetales , Plantas Medicinales , Xantina Oxidasa/efectos de los fármacos
4.
Phytomedicine ; 7(1): 31-8, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10782488

RESUMEN

Three major extracts from some traditional preparations, based on medicinal plants, used as antidiarrhoeal agents were investigated for their putative antiamoebic and spasmolytic activities in vitro. Results indicated that both biological activities are concentrated in the polyphenolic fraction, and not in the saponin or alkaloid containing fractions. The most active polyphenolic extracts were those from Euphorbia hirta whole plant, leaves of Alchornea cordifolia, Crossopteryx febrifuga, Nauclea latifolia, Psidium guajava, Tithonia diversifolia, stem bark of Harungana madagascariensis, Mangifera indica, Maprounea africana and Psidium guajava, inhibiting Entamoeba histolytica growth with MAC < 10 micrograms/ml. The same extracts, at a concentration of 80 micrograms/ml in an organ bath, also exhibited more than 70% inhibition of acetylcholine and/or KCl solution-induced contractions on isolated guinea-pig ileum.


Asunto(s)
Amebicidas/farmacología , Antidiarreicos/farmacología , Medicinas Tradicionales Africanas , Parasimpatolíticos/farmacología , Extractos Vegetales/farmacología , Plantas Medicinales , Animales , República Democrática del Congo , Entamoeba histolytica/efectos de los fármacos , Femenino , Cobayas , Íleon/efectos de los fármacos , Masculino , Pruebas de Sensibilidad Microbiana , Contracción Muscular/efectos de los fármacos
5.
Phytomedicine ; 6(1): 59-66, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10228613

RESUMEN

Forty six aqueous extracts from 38 medicinal plant species belonging to different families were selected on the basis of their traditional medicinal use as antidiarrhoeic agents. They were submitted in a broad biological screening including antibacterial, antiamoebic and antispasmodic activities. The results of the testing have indicated that 37 extracts (80.43%), 33 (71.74%) and 32 (69.54%) exhibited some level of antibacterial, antiamoebic and antispasmodic activity respectively. Only 8 plant extracts (17.39%) would act as antidiarrhoeic agents by a triple pronounced antibacterial, antiamoebic and antispasmodic action. They include aqueous extracts from Euphorbia hirta whole plant, leaves of Psidium guajava and Tithonia diversifolia, root bark of Alchornea cordifolia, Heinsia pulchella, Paropsia brazzeana, Rauwolfia obscura and Voacanga africana.


Asunto(s)
Antidiarreicos/aislamiento & purificación , Amebicidas/farmacología , Animales , Antibacterianos/farmacología , Antidiarreicos/farmacología , Bacterias/efectos de los fármacos , República Democrática del Congo , Entamoeba histolytica/efectos de los fármacos , Femenino , Cobayas , Íleon/efectos de los fármacos , Técnicas In Vitro , Masculino , Músculo Liso/efectos de los fármacos , Parasimpatolíticos/farmacología , Epidermis de la Planta/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Raíces de Plantas/química , Plantas Medicinales/química
6.
Planta Med ; 65(3): 213-7, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17260306

RESUMEN

A bioassay-guided fractionation of an 80% acetone extract from BRIDELIA FERRUGINEA stem bark showing a dose-dependent inhibitory effect towards both the classical and the alternative pathways of the complement system resulted in the isolation of a biflavanol (gallocatechin-(4'- O-7)-epigallocatechin) ( 1), 3,5-dicaffeoylquinic acid ( 2), 1,3,4,5-tetracaffeoylquinic acid ( 3), and a series of 3-methoxyflavone derivatives, including quercetin 3-methyl ether ( 4), quercetin 3,7,3',4'-tetramethyl ether ( 5), myricetin 3',4',5'-trimethyl ether ( 6; new compound) named ferrugin, myricetin 3,3',4',5'-tetramethyl ether ( 7), myricetin ( 8), and quercetin 3- O-glucoside ( 9) as the active constituents. Especially the biflavanol 1 and the caffeoyl esters of quinic acid 2 and 3 showed a strong inhibitory effect (IC (50) < 10 microM) on the classical pathway, compared to rosmarinic acid. Also on the alternative pathway, the biflavanol 1, the quinic acid derivatives 2 and 3, and some of the 3-methoxyflavones 5, 7 and 8 were more active than rosmarinic acid. The quinic acid derivatives were shown to be inhibitors of the C1 component and the terminal route of the complement system.

7.
J Ethnopharmacol ; 61(1): 57-65, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9687082

RESUMEN

Results from the in vitro antiamoebic activity of some Congolese plant extracts used as antidiarrhoeic in traditional medicine indicated that of 45 plant extracts tested, 35 (77.78%) exhibited an antiamoebic activity and 10 (22.22%) were inactive. The highest activity (MIC < 100 microg/ml) was obtained with extracts from root bark of Paropsia brazzeana, Cryptolepis sanguinolenta, Alchornea cordifolia, Hensia pulchella, Maprounea africana, Rauwolfia obscura and Voacanga africana, leaves and stem bark of Psidium guajava, stem bark of Dialum englerianum, Harungana madagascariensis and Mangifera indica, mature seeds of Carica papaya, and leaves of Morinda morindoides and Tithonia diversifolia. Metronidazole used as reference product showed a more pronounced activity than that of all plant extracts tested.


Asunto(s)
Amebicidas/farmacología , Entamoeba histolytica/efectos de los fármacos , Plantas Medicinales , Amebicidas/química , Animales , Antraquinonas/análisis , Antidiarreicos/farmacología , Antitricomonas/farmacología , Congo , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Entamoeba histolytica/crecimiento & desarrollo , Metronidazol/farmacología , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Extractos Vegetales/farmacología , Saponinas/análisis , Taninos/análisis
8.
Phytomedicine ; 5(3): 209-14, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-23195843

RESUMEN

From the 80% EtOH extract of Cryptolepis sanguinolenta (Lindl.) Schlechter (Periplocaeae) root bark, a cryptolepine isomer named neocryptolepine, and two dimeric alkaloids named biscryptolepine and cryptoquindoline were isolated. These compounds were tested for their putative antibacterial and antifungal activities. Results have indicated that neocryptolepine showed an antibacterial activity against Gram-positive bacteria (MIC < 100 µg/ml), but was less acive against Gram-negative bacteria. It also inhibited the growth of the yeast C. albicans. Biscryptolepine exhibited only an activity against some Gram-positive bacteria (MIC = 62.5 or 31 µg/ml) while cryptoquindoline did not shown an activity against all selected microorganisms. The antibacterial activity of neocryptolepine and biscryptolepine is bacteriostatic rather than bactericidal. No antifungal activity could be observed for all alkaloids in our test system at the highest test concentration of 100 µg/ml.

9.
Planta Med ; 63(3): 220-3, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9265193

RESUMEN

A kaempferol 7-O-rhamnosylsophoroside isolated from the leaves of Morinda morindoides showed dose-dependent complement-modulating properties towards both the classical (inhibiting effect) and alternative (activating effect) pathways of the complement system. Its structure was elucidated by chemical and spectroscopic methods as kaempferol 7-O-[alpha-L-rhamnopyranosyl-(1-->6)]-[beta-D-glucopyranosyl-(1-->2)]-be ta-D-glucopyranoside, a new natural product which was named morindaoside.


Asunto(s)
Activación de Complemento/efectos de los fármacos , Flavonoides , Glicósidos/química , Quempferoles , Plantas Medicinales , Quercetina/análogos & derivados , Secuencia de Carbohidratos , Glicósidos/aislamiento & purificación , Glicósidos/farmacología , Medicina Tradicional , Datos de Secuencia Molecular , Estructura Molecular , Hojas de la Planta , Quercetina/química , Quercetina/aislamiento & purificación , Quercetina/farmacología
10.
Planta Med ; 62(1): 22-7, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8720383

RESUMEN

In our biological screening of higher plants, an aqueous and an 80% EtOH extract from the root bark of Cryptolepis sanguinolenta showed potent antibacterial, anticomplementary, and moderate antiviral activities, but no antifungal effect could be detected. Bioassay-guided fractionation of the 80% EtOH extract led to the isolation of three alkaloids: quindoline (1), hydroxycryptolepine (2), cryptolepine.HCl (3), and the corresponding base cryptolepine (4). All compounds strongly inhibited the growth of Gram-positive bacteria (MIC < or = 100 micrograms/ml) and showed a moderate (MIC = 125 or 250 micrograms/ml), a weak (MIC = 500 micrograms/ml), or no activity (MIC > 500 micrograms/ml) against selected Gram-negative bacteria. They also possessed a bactericidal effect depending on the bacterial strain. Compounds 1, 2 and 3 displayed a dose-dependent inhibitory effect on the classical pathway of the complement system while compounds 2 and 3 activated the alternative pathway, except for compound 1. Compound 3 was found to possess an antiherpetic activity. Compounds 1 and 4 showed no antiviral effect, but were quite cytotoxic in the antiviral test system down to a concentration of 1 microgram/ml.


Asunto(s)
Alcaloides/farmacología , Antibacterianos/farmacología , Proteínas Inactivadoras de Complemento/farmacología , Raíces de Plantas/química , Plantas Medicinales/química , Alcaloides/química , Antibacterianos/química , Proteínas Inactivadoras de Complemento/química , Pruebas de Sensibilidad Microbiana , Análisis Espectral
11.
J Nat Prod ; 58(3): 372-8, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7775983

RESUMEN

In a screening program for complement classical pathway modulation, an 80% MeOH extract of the leaves of Morinda morindoides showed potent dose-dependent anticomplementary activity. Bioassay-guided chromatographic separation of the active constituents led to the isolation of ten flavonoids of which two were aglycones. The compounds were tested in vitro for their putative complement-inhibiting properties on the classical (CP) and the alternative (AP) pathways of the complement system. The results indicated that quercetin [1], quercetin 3-O-rhamnoside (quercitrin) [5], and quercetin 3-O-rutinoside (rutin) [7] showed similar anticomplementary activities (inhibition) on the CP of complement. A mixture of two kaempferol triglycosides isolated and denoted as M(015), also had a good inhibitory effect. The effects of these compounds were dose-dependent for this pathway. On the AP of complement, quercetin [1] and M(015) had, respectively, more pronounced inhibitory and activatory effects than the other tested flavonoids, but their effects were not dose-dependent for this pathway. The other isolated flavonoids showed weak effects or were inactive for both pathways.


Asunto(s)
Proteínas Inactivadoras de Complemento/farmacología , Plantas Medicinales/química , Animales , Vía Alternativa del Complemento/efectos de los fármacos , Vía Clásica del Complemento/efectos de los fármacos , Flavonoides/aislamiento & purificación , Flavonoides/farmacología , Cobayas , Hemólisis/efectos de los fármacos , Humanos , Técnicas In Vitro , Extractos Vegetales/farmacología , Hojas de la Planta/química , Conejos , Ovinos
12.
Ann Pharm Fr ; 48(4): 200-8, 1990.
Artículo en Francés | MEDLINE | ID: mdl-2080836

RESUMEN

A preliminary and anterior pharmacological study about 68 plant antidiarrheic traditional preparations, has proved the antispasmodic activity for 42 of them. Some extracts proceeding of these possess an antispasmodic activity, specially if they contain polyphenols (flavonoïds, catechics tanins), saponins and alkaloïds.


Asunto(s)
Antidiarreicos/farmacología , Parasimpatolíticos , Animales , República Democrática del Congo , Femenino , Cobayas , Íleon/fisiología , Masculino , Contracción Muscular/efectos de los fármacos , Músculo Liso/fisiología , Extractos Vegetales/farmacología
13.
Ann Pharm Fr ; 48(5): 255-63, 1990.
Artículo en Francés | MEDLINE | ID: mdl-2088161

RESUMEN

A preliminary and anterior bacteriological study about 38 plant antidiarrheic traditional preparations, has demonstrated that 35 of them have bactericidal activity. Thirty inhibit the growth of all select germs and 5 exert this bactericidal effect on some germs. Some extracts proceeding of these possess a bactericidal activity, specially if they contain polyphenols (flavonoids, catechics tanins), saponins and alkaloids.


Asunto(s)
Antidiarreicos/farmacología , Bacterias/efectos de los fármacos , Diarrea/tratamiento farmacológico , Extractos Vegetales/farmacología , Humanos , Prueba Bactericida de Suero
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA